Final answer:
While the popularity of credit card brands can fluctuate, Discover is often considered less widely accepted than Visa and Mastercard, potentially affecting its popularity. American Express sometimes faces similar issues due to higher merchant fees. However, credit, debit, and smart cards do not impact the overall money supply in the economy.
Step-by-step explanation:
Regarding the popularity of credit cards, it can vary over time due to a number of factors including consumer preferences, fees, rewards programs, and acceptance by merchants. While Visa, Mastercard, American Express, and Discover are all major credit card issuers, it is not accurate to state categorically that one of these is being replaced by the others without specific market data. However, it's important to note that Discover is often considered less universally accepted compared to Visa and Mastercard. American Express also has faced challenges due to its higher merchant fees. Businesses may opt not to accept these cards if the costs are too high, which could influence their popularity.
It's also crucial to understand that credit cards, debit cards, and smart cards are just methods of payment, and do not themselves represent money in the economy. Having more credit cards does not increase the amount of money in circulation, similar to how printing more checks doesn't increase the balance in a checking account.